Many buildings are built with space between the roof of the building and the living or working areas below the roof. Most houses have a peaked roof but a flat ceiling in the room or rooms directly below the roof. This creates an area between the roof and the ceiling of the room situated below that part of the roof, which is usually called an “attic.” Attics are sometimes used for storage of objects. Moreover, access must be provided from the living or working areas of a building to the attic in the event of a need to make repairs, to check on electrical wiring or heating and air conditioning ducts, and so on. Consequently, there is ordinarily some means of access provided for a user of a building to this attic space.
For most homes and garages, the most common access to the attic storage area consists of an opening in a ceiling. The opening is usually concealed by a trap door apparatus. Built into the trap door is a folding ladder. Therefore, to gain access to the attic, the trap door is pulled down, usually by a chain or a rope, which allows one access to the folded ladder. The ladder is unfolded with the bottom of the ladder now resting on the floor of the room below the trap door in the opening in the ceiling. One may then walk up the ladder through the opening into the attic area. The trap door is usually closed by a spring loaded hinge, which holds the trap door into the closed position until someone pulls on the chain or the rope that extends from the trap door into the from below. There are many disadvantages to this system. First, many people find a rope or chain hanging in to a living area to be unsightly. Second, the ladder is often narrow with rungs of no more than two or three inches in width. Third, the angle formed by the ladder and the floor on which it rests is usually much steeper than is the case for stairwells. Consequently, using the ladder means balancing one's feet on narrow rungs on a narrow ladder that is steeply angled to the floor on which the ladder rests. This makes it difficult to safely carry boxes of any size or weight from the living area into the attic area. Consequently, most attics are used for storage of such relatively light items as Christmas decorations, seasonal items, small boxes of clothes, empty luggage and other light weight items. Attics are rarely used for storage of substantial items such as household furniture, appliances, televisions, or other large or heavy items. The attic area is useable only by people who are capable of using a narrow, steep ladder. This excludes almost anyone with balance problems, people with bad knees, or people who have difficulty negotiating stairs.
A variety of expedients have been proposed as an alternative to the folding stairs. The most common expedient employs a framework attached to wood joists that may form a part of the ceiling of the room above the ceiling opening to the attic area. Mounted on this framework is a winch and cable drum attached at four corners to a lift platform. The winch can then be employed to raise or lower the lift platform. Once example of this type of device is seen in Bishop et al., U.S. Pat. No. 5,535,852. Here, a framework is built and mounted on a bracket to ceiling joists. There is a winch, employed at the top of the framework. A telescoping frame is also mounted to allow this telescoping frame to extend from the attic into the room below. The weight of any objects carried in the lift basket is supported by the ceiling joists on which the framework is mounted. A similar device is seen in Hughes, U.S. Pat. No. 5,667,035. Again, there are telescoping legs which extend from the ceiling into the area in the room below the ceiling. A lift platform is raised and lowered by a series of pulley mounted cables which attach to a winch. Penn, U.S. Pat. No. 6,962,236 employs a slidable, moveable frame, which may be slid away from the ceiling opening. Used in conjunction with the slidable, moveable frame is a foldable ladder which extends to the floor from the ceiling opening. When the framework is slid out of the way, the ladder may be used in the conventional fashion. However, when the framework is slid over the ceiling opening, a winch is used to raise and lower a lift platform mounted on slots along the now unfolded ladder. Again, the weight of the lift platform and any contents are supported by cables affixed to the moveable lift platform. The cables are raised and lowered by an electric winch. Sprague et al., U.S. Pat. No. 5,626,208 proposes a permanently mounted device for using a structure for moving objects between adjacent floors. There is a rail which extends from one floor through the ceiling into the adjacent area above. A worm gear is used to raise and lower a lift platform, which is mounted on the railing. The worm gear is turned by an electric motor. When not in use, the lift platform is ordinarily kept in the ceiling above the room in which the guide rail is mounted. This closes off the ceiling opening and prevents any inadvertent falls through the ceiling opening and also closes off what would otherwise be an unsightly hole in the ceiling.
Other devices have been proposed to raise and lower cargo into a storage area within an airplane. Courter, U.S. Pat. No. 3,478,904 proposes a folding device with a moveable lift platform mounted for slidable movement on the folding rails of the device. The lift platform is raised and lowered by cable winches mounted within the airplane. A somewhat similar device is seen in Molter et al., U.S. Pat. No. 3,861,542. The device folds into and deploys from a cargo bay in an airplane. Within the device is a cable-like device to raise and lower a platform on which a cargo container may be placed when the cargo container is in position to be moved into the airplane itself. The device hangs from the side of the airplane and is supported by the airplane structure. Similar type devices seen for cargo handling in airplanes are seen in Lang, U.S. Pat. No. 3,952,974, Carter et al., U.S. Pat. No. 4,586,684, and Goon, U.S. Pat. No. 5,076,515.
Despite these efforts there is still an unmet need for a device to make accessible an area between a roof and a ceiling. The device should operate automatically and provide for a powered lift of people and/or goods from one area to another. The device should be usable for existing homes with a trap door in the ceiling and should be usable in new construction. It should be built with a fail-safe safety feature so that should power fail or a part of the device break, it will not result in a sudden drop of goods or a person from the ceiling to the floor. It should require no physical effort to open, operate, utilize, or close. It should place no operating weight on the ceiling. When not in use, it should occupy no residential floor space nor should it be a permanent part of the residential area. It should meet existing building code requirements and existing safety codes. It should be useable by people with physical handicaps or with an inability to use prior art folding ladders.